PRECIS: Central corneal thickness (CCT) may increase over time in children affected by primary congenital glaucoma and treated with latanoprost for at least 30 months. PURPOSE: The purpose of this study was to investigate CCT modification over time in a population of primary pediatric glaucoma (PPG) patients prescribed a monotherapy of latanoprost. MATERIALS AND METHODS: The present paper reports the results of a post hoc analysis on patients enrolled in the Glaucoma Italian Pediatric Study (GIPSy). Children affected by PPG, with a postsurgical intraocular pressure between 22 and 26 mm Hg and treated with latanoprost monotherapy for at least 30 months were eligible for the analysis. CCT variation from baseline was investigated over the follow-up using univariable and multivariable longitudinal linear mixed models. The impact of age, sex, and intraocular pressure on CCT variation were evaluated taking into account the interaction of each variable with time. RESULTS: Twenty-seven eyes (20 patients) were included in the analysis. Mean duration of latanoprost treatment was 36.6 months (SD 2.5) and mean CCT at baseline was 551 μm (SD 37.7). A significant increase of CCT over time was revealed by multivariable analysis, taking into account the impact of age at baseline and its interaction with time (P=0.03). The interaction between age and time was significant (P=0.04), indicating that older age at baseline was associated with lower increase of CCT over time. No variation of CCT was found in univariable analysis (P=0.28). CONCLUSION: In this population of PPG patients treated with latanoprost for at least 30 months, CCT significantly increased over time, when the impact of age and its interaction with time were considered.